1. Field of the Invention
The invention relates to a Chaenomeles lagenaria extract and a method for extracting the same, and more particularly, to a Chaenomeles lagenaria extract that is effective in tumor growth inhibition and applicable to blood typing and method for extracting the same.
2. Description of the Related Art
The body is made up of many types of cells. Normally, cells grow and divide to produce more cells only when the body needs them. This orderly process helps keep the body healthy. However, some cells may keep dividing when new cells are not needed, these extra cells form a mass of tissue called a tumor. The tumor can be benign or malignant. Benign tumors can often be removed and cells from benign tumors do not spread to other parts of the body, rarely posing a threat to life. Malignant tumors, on the other hand are cancer. Cells in these tumors are abnormal and divide without control or order. They can invade and damage nearby tissues and organs. Also, cancer cells can break away from a malignant tumor and enter the bloodstream or the lymphatic system. As a result, cancer spreads from the original cancer site to form new tumors in other organs. According to statistics announced by the World Health Organization (WHO), more than 10 million people are diagnosed with cancer every year. Cancer causes 6 million deaths every year or 12% of deaths worldwide, and it is even estimated that there will be 15 million new cases every year by 2020.
Unfortunately, current therapies designed for the control and treatment of tumors in general, and malignant tumors in particular, are less than satisfactory. A variety of medical approaches including surgery, chemotherapy and radiotherapy are clearly unfocused and accompanied by unpleasant, and often quite serious, side effects as well as being characterized by limited effectiveness. Other treatment methods based on natural products are currently in use (Lee, K. H., Medical Research Review (1999) 19:569-596) or still in clinical trials (Levya, A., et al., Anticancer Research (2000) 20:1029-1031). These remedies, while they may be effective in particular instances, can hardly be considered to solve the overall problem.
Lectins have been used in a variety of scientific applications. They combine with single monosaccharides, usually in a terminal position in the glycolipid and glycoprotein component of the red cell membrane. Lectins have also been known to combine readily with carbohydrate in studies of erythrocytes, leukocytes, platelets, tissue cells and tumor cells, while some lectins are used as mitogens. Researches have found lectins which plays a role in targeting the tumor cells of certain tissues. In addition, most lectins possess multiple blood group specificities, but a few possess specificity for a single blood group determinant. Some lectins are comprised of a single protein that cross-reacts with two or more red cell surface receptors, whereas others can be separated into fractions, each with different blood group specificity.
Lectins (receptors specific proteins) are proteins present in plants (usually in seeds), invertebrate animals, some of the low vertebrate animals, algae, fungi, and bacteria. However, the role of lectins in living organisms is unclear. Goldstein et al. proposed that lectins are defined by their in vitro biological activities as “sugar-binding proteins or glycoproteins of non-immune origin which agglutinate cells and/or precipitate glycoconjugates”. Kocourek et al. suggested that lectins be defined as “sugar-binding proteins or glycoproteins of non-immune origin which are devoid of enzymatic activity towards sugar to which they bind and do not require free glycosidic hydroxyl groups on these sugars for their binding.”
Chaenomeles lagenaria is a native plant with bright red-orange colored flowers. The plant is also cultivated in Japan, so it is known as Japanese Quince. Since Chaenomeles lagenaria is rich in organic acids that inhibit bacteria growth, it has been made into Chinese herbal medicine and used internally and topically to treat pain; especially arthralgia and spasms, but also for skin irritation and swellings. Other researches have found that triperpenoid compounds, such as ursolic acid (UA) and oleanolic acid (OA) isolated and identified in the fruit of Chaenomeles lagenaria have shown marked anti-tumor effects on human colon carcinoma cell lines (Li, J., Guo W-J, Yang Q-Y, World Journal of Gastroenterology (2002);8(3):493-495). However, the studies of Chaenomeles lagenaria carried out so far have not focused on extracting a lectin or similar substance from Chaenomeles lagenaria nor are there any substantial studies relating to therapeutic effects of lectin extracted from Chaenomeles lagenaria. 
In search of a substance that is both effective in inhibiting tumor growth and applicable to binding to a specific red cell surface receptor, the lectin is extracted from Chaenomeles lagenaria to develop a therapeutic agent that meets the above demands with minimum side effects to the animal.